13564561920 has 480 divisors, whose sum is σ = 53700527232. Its totient is φ = 2860056576.

The previous prime is 13564561891. The next prime is 13564561951. The reversal of 13564561920 is 2916546531.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9084694 + ... + 9086186.

Almost surely, 2^13564561920 is an apocalyptic number.

13564561920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13564561920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26850263616).

13564561920 is an abundant number, since it is smaller than the sum of its proper divisors (40135965312).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13564561920 is a wasteful number, since it uses less digits than its factorization.

13564561920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1552 (or 1523 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 13564561920 in words is "thirteen billion, five hundred sixty-four million, five hundred sixty-one thousand, nine hundred twenty".